Additives for improving hydrocarbon recovery

ABSTRACT

Processes for recovering hydrocarbons from subterranean formations are disclosed. The hydrocarbon can be contacted with water or steam and one or more additives, and subsequently recovered. The hydrocarbon can be selected from the group consisting of heavy or light crude oil, bitumen, an oil sand ore, a tar sand ore and combinations thereof. The additive can be, for example, a fluorinated hydrocarbon, one or more alcohols, combinations of alcohols, and combinations of one or more alcohols and one or more fluorinated hydrocarbons. Compositions or mixtures including hydrocarbons, water or steam, and additives are also disclosed.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional of U.S. patent application Ser. No.13/554,515, filed Jul. 20, 2012, which claims priority to, and is acontinuation-in-part of, U.S. Ser. No. 13/158,919, which was filed onJun. 13, 2011, and titled ADDITIVES FOR IMPROVING HYDROCARBON RECOVERY,the contents of which are incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

THE NAMES OF THE PARTIES TO A JOINT RESEARCH AGREEMENT

Not applicable.

REFERENCE TO A SEQUENCE LISTING, A TABLE, OR A COMPUTER PROGRAM

Not applicable.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The disclosure pertains to hydrocarbon production, extraction orrecovery. In particular, the disclosure pertains to hydrocarbonproduction, extraction or recovery methods incorporating steam, waterand/or additives.

2. Description of the Related Art

At or beneath its surface, the earth contains deposits of crude oil andbituminous sands, known as tar sands or oil sands. If these deposits arelocated sufficiently close to the earth's surface, they can be recoveredusing surface or strip mining techniques. The mined ore typicallycontains about 10-15% bitumen, 80-85% mineral matter with the balancebeing water, and requires separation of the valued bitumen product fromthe mineral matter. This bitumen liberation process begins by initiallymixing or slurrying the ore with warm water in a hydrotransport line.The resultant slurry is then fed to a primary separation vessel or cell.In this separation process, additional warm water is added and themajority of the liberated bitumen will become attached to air bubbleswhere it is recovered by flotation. The bitumen liberation and recoveryprocess generally occurs at a pH of about 8.5, which is generallyobtained with the assistance of caustic soda. The coarse mineral matteris removed from the bottom of the vessel and a middlings portion,containing water, fine mineral matter, and suspended bitumen is sent forfurther bitumen recovery.

If the crude oil or bituminous sands are located sufficiently below thesurface of the earth, oil wells can be drilled to assist in theextraction of these materials. However, heavy hydrocarbons can provedifficult to recover or produce due to their high viscosities. Variousextraction, recovery, or production methods are known in the art such asflooding the formation with steam in an attempt to reduce the viscosityof the hydrocarbons to enable flow and aid in production.

One such method known as Cyclic Steam Simulation or the “huff-and-puff”method involves stages of infecting high pressure steam, soaking theformation, and production. The initial stage involves steam injectionfor a period of weeks to months to heat the hydrocarbon, bitumen orheavy oil resource in the reservoir, thereby reducing its viscosity suchthat it will be able to flow. Following injection, the steam is allowedto soak in the formation for a period of days to weeks to allow heat tofurther penetrate the formation. The heavy oil, sufficiently reduced inviscosity, is then produced from the same well until production beginsto decline upon which time the three step cycle is repeated.

Another recovery or production method used in the art is referred to assteam assisted gravity drainage (SAGD). The SAGD recovery method relieson two parallel, horizontal wells approximately 1 km in length. An upper“injector well” resides above a lower “producing well.” The producingwell is situated as close as possible to the bottom of the reservoir.Initially, steam is injected into both wells to begin heating theformation. After a period of time, the formation is sufficiently heatedsuch that the viscosity of the hydrocarbons or bitumen is reduced andthe hydrocarbons or bitumen are now able to enter the production well.Once this occurs, steam injection into the production well is ceased.

Low pressure steam is continuously injected into the injector well,resulting in the formation of a steam chamber, which extends laterallyand above as the process continues. At the edge of the steam chamber,the steam releases its latent heat into the formation. This processheats the hydrocarbons and/or bitumen causing it to be sufficientlyreduced in viscosity to drain along the edge of the steam chamber underthe influence of gravity to the lower producing well. It can then bepumped to the surface along with the result steam condensate. At thatpoint, the formed water and bitumen emulsion is separated.

In addition to imparting a viscosity reduction on the hydrocarbonsand/or bitumen, the steam condenses and a hydrocarbon-in-water emulsionforms showing the hydrocarbon to travel more readily to the producingwell. SAGD processes typically recover about 55% of the originalhydrocarbon or bitumen-in-place over the lifetime of the well.

Although this process has advantages, there are drawbacks as well. Forexample, with respect to bitumen production, the SAGD process relies onthe energy intensive production of steam to assist with bitumenrecovery. It requires natural gas, significant amounts of fresh water,and water recycling plants. Further, as the method relies upon gravitydrainage, production rates can be limited due to the high viscosity ofthe bitumen. Although the prior art has contemplated differentvariations to the SAGD process, such as the addition of certainadditives, the additives have not been successful and their presence hasresulted in, for example, emulsions of additive, water, and bitumen thatcannot be broken because the additives have caused the emulsion to bestable.

Therefore, seeking out additives that could increase the amount ofbitumen produced for the same steam input is highly desirable. Additivescould possess properties such as directly improving the heat efficiencywithin a formation as well as reducing the oil-water interfacialtension. Moreover, successful additives will lower the steam to oilratio meaning less steam will be necessary to produce the same amount ofbitumen due to the presence of the additive. Also, desirable additiveswill not interfere with the resulting emulsion such that it cannot bebroken. Finally, a successful additive should be volatile enough to becarried with the steam through the sand pack to reach the bitumen pay.

BRIEF SUMMARY OF THE INVENTION

A process for recovering a hydrocarbon from a subterranean formation isdisclosed. The subterranean formation can include any number of wells,such as two wells, three wells, etc. The disclosed process includes thesteps of contacting a hydrocarbon from a subterranean formation withsteam or water, contacting the hydrocarbon with one or more alcohols, orone or more fluorinated hydrocarbons, or a combination of one or morealcohols and one or more fluorinated hydrocarbons, and recovering thehydrocarbon. The hydrocarbon can be contacted by the steam or waterand/or the one or more alcohols, or one or more fluorinatedhydrocarbons, or combination of one or more alcohols and one or morefluorinated hydrocarbons, at any time during recovery of thehydrocarbon. The hydrocarbon is selected from the group consisting oflight or heavy crude oil, bitumen, an oil sand ore, a tar sand ore, andcombinations thereof. The hydrocarbon can be contacted with the steam orwater and one or more alcohols, or one or more fluorinated hydrocarbons,or a combination of one or more alcohols and one or more fluorinatedhydrocarbons, inside of the subterranean formation or outside of thesubterranean formation. The steam and the one or more alcohols, or oneor more fluorinated hydrocarbons, or combination of one or more alcoholsand one or more fluorinated hydrocarbons, can be injected into thesubterranean formation independently or as a mixture. The process can bea SAGD process that incorporates the addition of the one or morealcohols, or one or more fluorinated hydrocarbons, or a combination ofone or more alcohols and one or more fluorinated hydrocarbons.

A process for the recovery of bitumen from a subterranean formation isalso disclosed. The subterranean formation can include any number ofwells, such as two wells, three wells, etc. The process includes thesteps of contacting the bitumen with steam or water, contacting thebitumen with one or more alcohols, or one or more fluorinatedhydrocarbons, or a combination of one or more alcohols and one or morefluorinated hydrocarbons, and recovering the bitumen. The bitumen can becontacted by the steam or water and/or the one or more alcohols, or oneor more fluorinated hydrocarbons, or combination of one or more alcoholsand one or more fluorinated hydrocarbons, at any time during recovery ofthe bitumen. The bitumen can be contacted with the steam or water andone or more alcohols, or one or more fluorinated hydrocarbons, orcombination of one or more alcohols and one or more fluorinatedhydrocarbons, inside of the subterranean formation or outside of thesubterranean formation. The steam and the one or more alcohols, or oneor more fluorinated hydrocarbons, or combination of one or more alcoholsand one or more fluorinated hydrocarbons, can be injected into thesubterranean formation independently or as a mixture. The process can bea SAGD process that incorporates the one or more alcohols, or one ormore fluorinated hydrocarbons, or a combination of one or more alcoholsand one or more fluorinated hydrocarbons.

A composition or mixture of components is also disclosed. Thecomposition or mixture includes a hydrocarbon, water or steam, and oneor more alcohols, or one or more fluorinated hydrocarbons, or acombination of one or more alcohols and one or more fluorinatedhydrocarbons. The hydrocarbon can be selected from the group consistingof light or heavy crude oil, bitumen, an oil sand ore, a tar sand ore,and combinations thereof.

The foregoing has outlined rather broadly the features and technicaladvantages of the present invention in order that the detaileddescription of the invention that follows may be better understood.Additional features and advantages of the invention will be describedhereinafter that form the subject of the claims of the invention. Itshould be appreciated by those skilled in the an that the conception andthe specific embodiments disclosed may be readily utilized as a basisfor modifying or designing other embodiments for carrying out the samepurposes of the present invention. It should also be realized by thoseskilled in the art that such equivalent embodiments do not depart fromthe spirit and scope of the invention as set forth in the appendedclaims.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

A detailed description of the invention is hereafter described withspecific reference being made to the drawings in which:

FIG. 1 is a one-way analysis of bitumen extracted (%) vs. blank andtrifluoroethanol.

FIG. 2 is a one-way analysis of bitumen extracted (%) vs. ethanol andtrifluoroethanol.

FIG. 3 is a one-way analysis of bitumen extracted (%) vs. blank, ethanol(1,000 ppm), and trifluoroethanol (1,000 ppm).

FIG. 4 shows comparative data for the blank, methanol, ethanol andn-alcohols, propanol, butanol and pentanol. All alcohols were dosed at1,000 ppm.

FIG. 5 shows comparative data for the C₅ alcohol derivatives. Alladditives were dosed at 1,000 ppm.

DETAILED DESCRIPTION OF THE INVENTION

This disclosure relates to methods of producing or recoveringhydrocarbons, such as light or heavy crude oil, bitumen, and oil or tarsand ores. Compositions and mixtures including the produced or recoveredhydrocarbons are also disclosed herein.

It has been found that addition of additives, such as fluorinatedhydrocarbons, greatly enhances hydrocarbon extraction. In the presentapplication, hydrocarbon is understood to mean viscous or heavy crudeoil, light crude oil, tar sands or oil sands oil, or bitumen.

It has also been found that addition of additives, such as one or morealcohols, greatly enhances hydrocarbon extraction.

Further, it has been found that addition of additives, such as certaincombinations of one or more alcohols or combinations of one or morealcohols and one or more fluorinated hydrocarbons greatly enhanceshydrocarbon extraction.

A process for recovering a hydrocarbon is disclosed involving twoparallel, horizontal wells. The wells can be, for example, approximately1 km in length, but other lengths are acceptable as well. The processcan be an SAGD process or any other suitable process. An upper injectorwell resides above a lower producing well in the SAGD process. The wellscan be separated by any suitable distance, for example, approximately4-6 meters. Initially, steam is injected downhole into one or both ofthe wells where it condenses and begins heating the formation and thehydrocarbon(s) therein. Generally, steam is injected into the well headand this process is readily understood by those skilled in the art. Thesteam can be injected at high pressures and can be at a temperature ofabout 500° C. After a period of time, the formation is sufficientlyheated such that the viscosity of the hydrocarbon is reduced.

Over time, low pressure steam can be continuously injected into theinjector well, resulting in the formation of a steam chamber, furtherheating the hydrocarbon causing it to be sufficiently reduced inviscosity to drain along the edge of the steam chamber to the lowerproducing well by way of gravity where it can be pumped to the surfacealong with the condensed steam and/or the additive(s). At that point,the water and/or additive(s) are separated from the hydrocarbon in wateremulsion and the hydrocarbon can be recovered using various knownmethods in the art such as “breaking” the emulsion.

An additive according to the present disclosure, such as a fluorinatedhydrocarbon, one or more alcohols, or combinations of one or morealcohols and one or more fluorinated hydrocarbons, can also be injectedinto either one of the wells, or both of the wells. The additive(s) canbe injected independently of the steam or it can be added as a mixturewith the steam. The steam may be injected continuously or intermittentlyinto one or both of the wells. Moreover, the additive(s) may be injectedcontinuously or intermittently into one or both of the wells. Also, ifthe steam and additive(s) are added as a mixture, the mixture can beadded either continuously or intermittently into one or both of thewells.

Additive(s) addition may occur at, but is not limited to, the steamheader, at the well head, or it can be added into the boiler feed water.

The additive(s) can be injected into one or both of the wells at anypoint during production such as when production begins or whenproduction begins to diminish. For example, when hydrocarbon productionbegins to decline in the well, the additive(s) described herein can beadded. By adding the additive(s) after production has begun to decline,the recovery level can be brought back to or near an optimal or peakhydrocarbon recovery level.

A process for the recovery of bitumen from a subterranean formation isalso disclosed. The process can be a SAGD process and the bitumen can berecovered from a hydrocarbon bearing ore, such as oil sands or tarsands. The process may involve two parallel, horizontal wells, which aredrilled in an oil sand or tar sand formation. The wells can be, forexample, approximately 1 km in length, but other lengths are acceptableas well. An upper injector well resides above a lower producing well.The wells cast be separated by any suitable distance, for example,approximately 4-6 meters. Initially, steam is injected downhole into oneor both of the wells where it condenses and begins heating the formationand the bitumen therein. Generally, steam is injected into the well headand this process is readily understood by those skilled in the art. Thesteam condenses and heats the formation and the bitumen residingtherein. The steam can be injected at high pressures and can be at atemperature of about 500° C. After a period of time, the formation issufficiently heated such that the viscosity of the bitumen is reduced.

Over time, low pressure steam can be continuously injected into theinjector well, resulting in the formation of a steam chamber, furtherheating the bitumen causing it to be sufficiently reduced in viscosityto drain along the edge of the steam chamber to the lower producing wellby way of gravity where it can be pumped to the surface along with thecondensed steam and/or the additive(s). At that point, the water and/oradditive(s) are separated from the bitumen in water emulsion and thebitumen can be recovered using various known methods in the art such as“breaking” the emulsion.

An additive according to the present disclosure, such as one or morefluorinated hydrocarbons, one or more alcohols, or combinations of oneor more alcohols and one or more fluorinated hydrocarbons, can also beinjected into either one of the wells, or both of the wells, to contactthe bitumen. The additive(s) can be injected independently of the steamor can be added as a mixture with the steam. The steam may be injectedcontinuously or intermittently into one or both of the wells. Moreover,the additive(s) may be injected continuously or intermittently into oneor both of the wells. Also, if the steam and additive(s) are added as amixture, the mixture can be added either continuously or intermittentlyinto one or both of the wells.

Additive(s) addition may occur at, but is not limited to, the steamheader, at the well head, or it can be added into the boiler feed water.

The additive(s) can be injected into one or both of the wells at anypoint during recovery such as when production begins or when productionbegins to diminish. For example, when bitumen production begins todecline in the well, the additive(s) described herein can be added. Byadding the additive(s) after production has begun to decline, therecovery level can be brought back to or near an optimal or peak bitumenrecovery level.

It is noted that when carrying out the recovery or production methodsdisclosed herein, any number of wells, such as two wells, three wells,even a single well, can be used. No matter the number of wells selected,the steam and additive(s) described herein can be injected into any ofthe wells, or all of the wells. The additive(s) can be injectedindependently of the steam or it can be added as a mixture with thesteam into any of the wells. The steam may be injected continuously orintermittently into any of the wells. Moreover the additive(s) may beinjected continuously or intermittently into any of the wells. Also, ifthe steam and additive(s) are added as a mixture, the mixture can beadded either continuously or intermittently into any of the wells.

Also, hydrocarbons can be mined or extracted from a formation and thehydrocarbon can be separated outside of the formation using any knownmethod in the art such as, for example, a primary separation vessel.Such a separation process can be carried out with the assistance ofheated water, the additive(s) disclosed herein, and optionally otheradditives, such as caustic soda. In certain variations, the hydrocarbonsare led into hydrotransport lines and contacted therein by the heatedwater and optionally the additive(s), which conditions the ore andstarts the bitumen liberation process. The resultant slurry can then befed into one or more primary separation vessels. A hydrocarbon primaryfroth is separated at the top of the vessel while the sand settles atthe bottom. The hydrocarbon froth is then subjected to furtherprocessing.

The contents other than those in the hydrocarbon primary froth can gothrough secondary separation processes where further hydrocarbon can berecovered.

The additives(s) disclosed herein can be added either separately, or asa mixture with the heated water, at any time during primary, secondary,and/or tertiary separation or recovery, to enhance the hydrocarbonrecovery and/or minimize the amount of water used.

Further, bitumen can be mined or extracted from a formation and thebitumen can be separated from, for example, oil or tar sand, outside ofthe formation using any known method in the art such as, for example, aprimary separation vessel. Such a separation process can be carried outwith the assistance of heated water, the additive(s) disclosed herein,and optionally other additives, such as caustic soda. In certainvariations, the oil or tar sand bitumen is fed into hydrotransport linesand contacted therein by the heated water and optionally theadditive(s), which conditions the ore and starts the bitumen liberationprocess. The resultant slurry can then be fed into one or more primaryseparation vessels. A bitumen primary froth is separated at the top ofthe vessel while the sand settles at the bottom. The bitumen froth isthen subjected to further processing.

The contents other than those in the bitumen primary froth can gothrough secondary separation processes where further bitumen can berecovered.

The additive(s) disclosed herein can be added either separately, or as amixture with the heated water, at any time daring separation orsecondary separation, to enhance the bitumen recovery and/or minimizethe amount of water or used.

Compositions are also disclosed herein. The compositions can include oneor more hydrocarbons, water or steam, and one or more additive(s). Theadditive(s) can be the additives described in the present application,such as the fluorinated hydrocarbon additives, one or more alcoholadditives, or combinations of one or more alcohols and one or morefluorinated hydrocarbons. Such a composition can be obtained from asubterranean formation by contacting one or more hydrocarbons in asubterranean formation with heated water or steam, contacting the one ormore hydrocarbons in the subterranean formation with additive(s), suchas one or more fluorinated hydrocarbons, one or more alcohols, orcombinations of one or more alcohols and one or more fluorinatedhydrocarbons, as described herein, and recovering the resulting emulsionfrom the formation. Such a composition can also be obtained bycontacting the hydrocarbon with water or steam, as well as additive(s),such as one or more fluorinated hydrocarbons, one or more alcohols, orcombinations of one or more alcohols and one or more fluorinatedhydrocarbons, as described herein, outside of the subterraneanformation.

Also disclosed is a composition including water or steam, an additive,such as one or more fluorinated hydrocarbons, one or more alcohols, orcombinations of one or more alcohols and one or more fluorinatedhydrocarbons, as described herein, and bitumen. Such a composition canbe obtained from a subterranean formation by contacting bitumen in asubterranean formation with heated water or steam, contacting thebitumen in the subterranean formation with the additive(s), andrecovering the resulting emulsion from the formation. The water or steamand additive can be added independently of each other or can be added asa mixture. Such a composition can also be obtained by contacting thebitumen with water or steam, as well as an additive, outside of thesubterranean formation.

Various additives are contemplated by the present disclosure. Theadditive disclosed herein can be, for example, one or more fluorinatedhydrocarbons. Typically, unless surface or strip mining techniques arebeing used, the fluorinated hydrocarbon has an atmospheric boiling pointof less than or equal to about 300° C. The fluorinated hydrocarbonshould have volatility sufficient to allow for delivery to theproduction front unless surface or strip mining techniques are beingused. Examples of fluorinated hydrocarbon additives useful in connectionwith the present disclosure include, but are not limited to,trifluoroethanol, trifluoropropanol, trifluorobutanol,allylhexafluoroisopropanol, hexafluoroisopropanol, trifluoroacetic acid,methyl trifluoroacetate, ethyl trifluoroacetate, isopropyltrifluoroacetate, trifluoroacetaldehydemethyl hemiacetal,trifluoroacetaldehyde ethyl hemiacetal, trifluoroacetic anhydride,trifluoroacetone, fluorotoluene, and any combination or mixture thereof.Typically, the one or more fluorinated hydrocarbons are added at aconcentration from about 25 to about 50,000 ppm by weight of thefluorinated hydrocarbon in the steam (wt/wt fluorinated hydrocarbonadditive to steam basis). Another possible dosage of the fluorinatedhydrocarbon is from about 1,000 ppm to about 5,000 ppm, and anotherpossible dosage is from about 100 to about 1,000 ppm.

Even further, other additives are contemplated by the presentdisclosure. The additives disclosed herein can be, for example, one ormore alcohols. Typically, unless surface or strip mining techniques arebeing used, the one or more alcohols have an atmospheric boiling pointof less than or equal to about 300° C. The one or more alcohols shouldhave volatility sufficient to allow for delivery to the production frontunless surface or strip mining techniques are being used. Examples ofalcohol additives useful in connection with the present disclosureinclude, but are not limited to, C₁ alcohols (i.e. methanol), C₂alcohols, C₃ alcohols, C₄ alcohols, C₅ alcohols, C₆ alcohols, C₇alcohols, C₈ alcohols, C₉ alcohols, or C₁₀ alcohols, C₁₁ alcohols, C₁₂alcohols, C₁₃ alcohols, C₁₄ alcohols, C₁₅ alcohols, and any combination,mixture, or isomer thereof. For example, the alcohol additives could beany combination of C₁-C₁₅ alcohols, or any combination of C₂-C₇alcohols, or any combination of C₈-C₁₅ alcohols, or any combination ofC₂-C₅ alcohols, etc. Useful additives in accordance with the presentdisclosure can also be defined as methanol, ethanol, 1-propanol,1-butanol, 1-pentanol, 2-pentanol, 3-methyl-1-butanol,2-methyl-1-butanol, 2-methyl-2-butanol, or any combination thereof.Further, any of the aforementioned alcohol additives can be addedtogether as a mixture and any of the aforementioned fluorinatedhydrocarbon additives can also be added into the mixture.

For example, in an aspect, the additive used in the disclosed processcan be ethanol. In another aspect, the additive used can be 1-butanol.In another aspect, the additive used can be 2-pentanol. In anotheraspect, the additive used can be a mixture of propanol, butanol, and1-pentanol. In another aspect, the additive used can be a mixture oftrifluoroethanol (TFE) and ethanol. In another aspect, the additive usedcan be a mixture of trifluoroethanol (TFE) and butanol. In anotheraspect, the additive used can be a mixture of ethanol and 1-pentanol. Aspreviously noted, any combination of one or more alcohols or anycombination of one or more fluorinated hydrocarbons can be used inaccordance with the processes disclosed herein, and even further, anycombination of one or more alcohols combined with one or morefluorinated hydrocarbons can be used.

Typically, the one or more alcohols are added at a concentration fromabout 25 to about 50,000 ppm by weight of the one or more alcohols, orcombination of one or more alcohols and one or more fluorinatedhydrocarbons, in the steam (wt/wt additive (alcohol, combination ofalcohols, or combination of one or more alcohols with one or morefluorinated hydrocarbons) additive to steam basis). One possible dosageof the one or more alcohols additive, or the one or more alcoholscombined with one or more fluorinated hydrocarbons additive, is fromabout 500 ppm to about 2,000 ppm, and another possible dosage is about1,000 to about 2,000 ppm. Also, it is possible to add the additive at adosage of 1,000 ppm by weight of the additive in the steam.

The foregoing additives or combinations of additives increase the amountof bitumen produced for the same steam input. Without wishing to bebound by any theory, it is considered that these additives orcombinations of additives could possess properties such as directlyimproving the heat efficiency within a formation as well as reducing theoil-water interfacial tension. Moreover, the disclosed additives orcombinations of additives will lower the steam to oil ratio meaning lesssteam will be necessary to produce the same amount of hydrocarbon orbitumen, or additional hydrocarbon or bitumen will be produced for thesame steam input, due to the presence of the additive(s). Further, theseadditives or combinations of additives will not interfere with theresulting emulsion such that it cannot be broken. When the emulsionproduct is recovered from the formation, it must be broken to obtain thedesired hydrocarbons. It has been found that certain amine additives caninterfere with this process such that the produced emulsion cannot bebroken and therefore, the desired hydrocarbon(s) cannot readily beobtained. The additive(s) of the present disclosure overcome thisproblem. Finally, the presently disclosed additives or combinations ofadditives are volatile enough to be carried with the steam through thesand pack to reach the bitumen pay.

Processes wherein the additive(s) or combinations of additives of thepresent disclosure can be beneficial to the hydrocarbon recoveryinclude, but are not limited to, cyclic steam stimulation, steamassisted gravity drainage, vapor recovery extraction methods, mining orextraction techniques, and the like.

The foregoing may be better understood by reference to the followingexamples, which are intended only for illustrative purposes and are notintended to limit the scope of the invention.

Example 1

A sample of oilsands ore (15 g) was charged into a pre-weighed stainlesssteel holder containing several holes. The oilsands ore contained 13.51%bitumen, 83.45% solids and 3.04% water. A cellulose thimble to accountfor any solids extracted as a consequence of the method, approximately 4cm in length, was placed beneath the stainless holder and the two wereplaced into a jacket Soxhlet extractor. Deionized water or processboiler feed water (BFW), as specified, (300 mL) and trifluoroethanolwere charged into a 500 mL round bottom flask beneath the extractorunit. Blank runs were additionally conducted in the same mannerexcluding trifluoroethanol. The extractor and round bottom flask werewrapped with insulation and aluminum foil, and the extraction run athigh temperature for 4 hours. The extraction was then allowed to cool,the stainless bolder removed, wiped of any extracted bitumen, andallowed to dry in a 105° C. oven for 2 days. The cellulose thimblecontaining any solids extracted as a consequence of the extractionprocess was placed in the oven to dry overnight.

Following drying in the oven, the stainless holder and cellulose thimblewere allowed to cool to room temperature and weighed. The amount ofbitumen extracted was determined based on the amount of bitumeninitially present in the ore, accounting for solids losses in theextraction process and water losses in the oven. To determine the amountof bitumen extracted, it was assumed that 66% of the connate water inthe original ore sample would be lost over a 2 day period in the oven(Equation 1).

$\begin{matrix}{{Bitumen}\mspace{14mu}{extracted}\mspace{14mu}(\%)\mspace{14mu}{using}\mspace{14mu}{Test}\mspace{14mu}{Method}\mspace{14mu}{A.}} & \; \\{\mspace{860mu}{{Equation}{\mspace{11mu}\;}1}} & \; \\\begin{matrix}{{{Bitumen}\mspace{14mu}{Extracted}\mspace{14mu}(\%)} = {\frac{\begin{matrix}{{Ore}\mspace{14mu}{assuming}{\mspace{11mu}\;}66\%\mspace{14mu}{of}} \\{\mspace{11mu}{{connate}{\mspace{11mu}\;}H_{2}O\mspace{14mu}{lost}\mspace{14mu}(g)}}\end{matrix}\; - \begin{matrix}\left( {{{Final}\mspace{14mu}{ore}\mspace{14mu}(g)} +} \right. \\\left. {{Dried}\mspace{14mu}{solids}\mspace{14mu}{extracted}\mspace{14mu}(g)} \right)\end{matrix}}{{Initial}\mspace{14mu}{bitumen}\mspace{14mu}{in}\mspace{14mu}{ore}\mspace{14mu}(g)} \times 100{\%.}}}\end{matrix} & \;\end{matrix}$

Dosages of 500 or 1,000 ppm of trifluoroethanol (based on the water)were tested (FIG. 1 and Table 1). The mean bitumen extracted for theblank (n=5) was 15.06% (SD=1.87%), the 500 ppm dose (n=8) was 26.53%(SD=5.99), 1,000 ppm dose in deionized water (n=3) was 29.11%(SD=8.20%), and 1,000 ppm in BFW was 37.38% (SD=6.37%) (Table 1). All ofthe trifluoroethanol additions resulted in p-values of less than 0.05when compared to the blank, and were considered to be statisticallysignificant (Table 2).

TABLE 1 Mean, standard deviation and number of runs for thetrifluoroethanol runs. Number of Mean Bitumen Level Runs Extracted (%)Std Dev Blank 5 15.06 1.87 Trifluoroethanol 1,000 ppm 3 29.11 8.20Trifluoroethanol 1,000 ppm BFW 3 37.38 6.37 Trifluoroethanol 500 ppm 826.53 5.99

TABLE 2 p-values comparing the trifluoroethanol and blank runs. Level−Level p-Value Trifluoroethanol 1,000 ppm BFW Blank <.0001*Tritluoroethanol 1,000 ppm Blank 0.0040* Trifluoroethanol 500 ppm Blank0.0029*

Example 2

A comparison between ethanol and trifluoroethanol was carried out (bothdosed at 500 ppm). Ethanol (n=6) resulted in a mean bitumen extracted of21.04% (SD=3.88%) while the same dose of trifluoroethanol (n=8) resultedin 26.53% (SD=5.99%) bitumen extracted (FIG. 2 and Table 3). The blankvalues were as above. Considering this data, trifluoroethanoloutperforms both ethanol and the blank, with p-values of less than 0.05in both cases (Table 4).

TABLE 3 Mean, standard deviation, and number of runs for the ethanol andtrifluoroethanol runs. Number of Mean Bitumen Level Runs Extracted (%)Std Dev Blank 5 15.06 1.87 Ethanol 6 21.04 3.88 Trifluoroethanol 8 26.535.99

TABLE 4 p-values for the trifluoroethanol and blank runs. Level −Levelp-Value Trifluoroethanol Blank 0.0005* Ethanol Blank 0.0482*Trifluoroethanol Ethanol 0.0428*

Example 3

Oilsands ore (15 g) was charged into a stainless holder containingseveral holes on the bottom and an open top. For these experiments,extraction glassware that enabled direct contact of steam andvolatilized additive with the ore was used. Deionized water (200 mL) andtrifluoroethanol (1,000 ppm based on the water) were added to the roundbottom portion of extraction glassware. Directly above the round bottomportion of the extraction flask sat a coarse stainless steel grid tosupport the holder containing the oilsands ore sample. The extractionflask was wrapped with insulation and aluminum foil and the experimentwas refluxed for 4 h. The collected bitumen in water was separated usinga rotary evaporator (rotovap) and subsequently extracted with tolueneinto a 100 mL volumetric flask. Bitumen adhered to the sides of theflask was extracted with toluene and added to the bitumen obtainedfollowing rotovap separation. The bitumen on the sides of the stainlessholder was accounted for by collecting with a pre-weighed cleaningtissue. The pH of the water following rotovap separation was measured.

Following this initial extraction, the same stainless holder with orewas added back to extraction vessel along with fresh deionized water(200 mL) and trifluoroethanol (1,000 ppm). The experiment was carriedout in the same manner as the first incremental extraction. This testwas repeated a third time with the same stainless holder and ore.Following the three incremental recoveries, the remaining bitumen in theore was determined by Dean-Stark extraction with toluene. A blank wasalso run in the same manner without trifluoroethanol.

The bitumen extracted with steam for each increment (runs 1-3) wascompared to the total bitumen extracted and expressed as % bitumenextracted (Equation 2). The total bitumen extracted with steam for thethree runs was compared to the total bitumen extracted and expressed as% total bitumen extracted (Equation 3).

$\begin{matrix}{{Incremental}{\mspace{11mu}\;}{bitumen}\mspace{14mu}{extracted}\mspace{14mu}{calculation}{\mspace{11mu}\;}{for}{\mspace{11mu}\;}{runs}\mspace{14mu} 1\text{-}3.} & \; \\{\mspace{860mu}{{Equation}\mspace{14mu} 2}} & \; \\\begin{matrix}{{{Bitumen}{\mspace{11mu}\;}{Extracted}\mspace{14mu}{Run}\mspace{14mu} 1(\%)} = {\frac{{Bitumen}{\mspace{11mu}\;}{extracted}{\mspace{11mu}\;}{with}\mspace{14mu}{steam}\mspace{14mu}{run}\mspace{14mu} 1\mspace{14mu}(g)}{\begin{matrix}{{Total}{\mspace{11mu}\;}{bitumen}{\mspace{11mu}\;}{extracted}} \\{{with}\mspace{14mu}{steam}\mspace{14mu}{runs}{\mspace{11mu}\;}1\text{-}3\mspace{14mu}(g)}\end{matrix} + \begin{matrix}{{Bitumen}\mspace{14mu}{extracted}} \\{{with}\mspace{14mu}{{toluene}{\mspace{11mu}\;}(g)}}\end{matrix}} \times 100{\%.}}}\end{matrix} & \; \\{{Total}\mspace{14mu}{bitumen}\mspace{14mu}{extracted}\mspace{14mu}{calculation}{\mspace{11mu}\;}{for}{\mspace{11mu}\;}{incremental}\mspace{14mu}{recovery}\mspace{11mu}{{test}.}} & \; \\{\mspace{860mu}{{Equation}{\mspace{11mu}\;}3}} & \; \\\begin{matrix}{{{Total}{\mspace{11mu}\;}{Bitumen}{\mspace{11mu}\;}{Extracted}\mspace{14mu}(\%)} = {\frac{{Total}\mspace{14mu}{Bitumen}{\mspace{11mu}\;}{extracted}{\mspace{11mu}\;}{with}\mspace{14mu}{steam}\mspace{14mu}{run}\mspace{14mu} 1\text{-}3\mspace{14mu}(g)}{\begin{matrix}{{Total}{\mspace{11mu}\;}{bitumen}{\mspace{11mu}\;}{extracted}} \\{{with}\mspace{14mu}{steam}\mspace{14mu}{runs}{\mspace{11mu}\;}1\text{-}3\mspace{14mu}(g)}\end{matrix} + \begin{matrix}{{Bitumen}\mspace{14mu}{extracted}} \\{{with}\mspace{14mu}{{toluene}{\mspace{11mu}\;}(g)}}\end{matrix}} \times 100{\%.}}}\end{matrix} & \;\end{matrix}$

Following the first run, the blank extracted 28.60% of the bitumen inthe sample whereas the trifluoroethanol extracted 26.40%. Consideringthis test method, the efficacy of trifluoroethanol can be seen in thesecond and third runs. The bitumen extracted for the blank runs 2 and 3was 11.79% and 5.46%, respectively. The bitumen extracted when usingtrifluoroethanol does not decline as rapidly, with 17.80% and 14.05%bitumen being extracted for runs 2 and 3, respectively. The overallbitumen extracted for the blank was 45.84% and with trifluoroethanol was58.25%. Results are shown in Table 5.

TABLE 5 Incremental bitumen extracted results for the blank andtrifluoroethanol (1,000 ppm). Bitumen Bitumen Bitumen Total ExtractedExtracted Extracted Bitumen Additive pH (Run 1) pH (Run 3) pH (Run 3)Run 1 (%) Run 2 (%) Run 3 (%) Extracted (%) Blank 8.94 8.65 9.19 28.6011.79 5.46 45.84 Trifluoroethanol 8.78 8.87 8.79 26.40 17.80 14.05 58.25

Example 4

Deionized water (100 mL) and trifluoroethanol (1,000 ppm based on thewater) were charged into a laboratory autoclave reader with a volumecapacity of 600 mL and fit with a glass liner. A 15 g oilsands oresample, with the same composition as in Example 1, was added to astainless holder with several holes on the bottom and an open top. Thesample was placed above the water/trifluoroethanol mixture so as to notdirectly contact the water and trifluoroethanol prior to the start ofthe experiment. The reactor was sealed and heated to 200° C. to 5 hours.During this time, the internal pressure of the vessel reached 200 psig.The reactor was then allowed to cool to room temperature, opened, andthe water was separated from the bitumen. The resulting bitumen wasextracted with toluene into a 100 mL volumetric flask. Any bitumenremaining on the outside of the stainless holder was accounted for bycollecting onto a pre-weighed cleaning tissue. The remaining bitumen inthe ore sample was then determined by Dean-Stark extraction withtoluene. A blank was also run in the same manner withouttrifluoroethanol. The resulting bitumen extracted for the blank wasfound to be 6.42% and with the addition of trifluoroethanol, extractionincreased to 13.05%.

Example 5

Bitumen extraction studies for Examples 5-8 were carried out accordingto the following procedures. These examples used a glass laboratoryextraction vessel that enabled steam and volatilized additive todirectly contact the core sample. For these experiments, 15 g of coresample was added to a stainless holder containing several holes and aclosed top. Previous experiments using this extraction vessel were runwith the stainless holder having an open top. The core sample had acomposition of 15.23% bitumen, 83.58% solids, and 1.37% water (based onthe average of five Dean-Stark runs). Deionized water (200 mL) and/oradditive(s) were added to the round bottom portion of the extractionvessel. The vessel was fitted with insulation and sufficient heat wasapplied to allow the contents to reflux for 4 hours at ambient pressure.The additive(s) dosage was based on the concentration in water.Following the experiment, the water was separated from the collectedbitumen. The bitumen component remained in the vessel, was removed withtoluene, and subsequently placed into a 100 mL volumetric flask. Thebitumen on the sides of the stainless holder was accounted for bycollecting with a pre-weighed cleaning tissue. The amount of bitumenremaining in the core following steam extraction was determined byDean-Stark extraction with toluene. The bitumen recovered with steam, orsteam together with additive(s), was compared to the total bitumen inthe sample and expressed as % bitumen extracted (Equation 4).

$\begin{matrix}{{Bitumen}\mspace{14mu}{extraction}\mspace{14mu}{calculation}\mspace{14mu}{for}\mspace{14mu}{example}\mspace{14mu} 5\text{-}8.} & \; \\{\mspace{855mu}{{Equation}{\mspace{11mu}\;}4}} & \; \\\begin{matrix}{{{Bitumen}\mspace{14mu}{Extracted}\mspace{14mu}(\%)} = {\frac{{Bitumen}\mspace{14mu}{extracted}\mspace{14mu}{with}\mspace{14mu}{steam}\mspace{14mu}(g)}{{\begin{matrix}{{{Bitumen}\mspace{14mu}{extracted}}{\;\;}} \\{{with}\mspace{14mu}{steam}\mspace{14mu}(g)}\end{matrix}\; + \begin{matrix}{{Bitumen}\mspace{14mu}{extracted}} \\{{with}\mspace{14mu}{toluene}\mspace{11mu}(g)}\end{matrix}}\mspace{14mu}} \times 100{\%.}}}\end{matrix} & \;\end{matrix}$

In Example 5, using just water for reflux (blank) resulted in a meanbitumen extracted of 6.2% (Table 6). Addition of the alcohol additivessignificantly improved the bitumen extraction. The majority of thestudies were carried out at a dosage of 1,000 ppm (based on the waterfraction). When blends were studied they were also conducted to total1,000 ppm product dosage, however some runs were carried out at a totalproduct dosage of 1,500 or 2,000 ppm in subsequent examples.

Experimental runs were carried out to compare the performance of ethanol(200 proof) to trifluoroethanol. Runs without additive (n=5) resulted ina mean bitumen extraction of 6.2±1.7%. Addition of 1,000 ppm of ethanol(n=3) resulted in a mean bitumen extraction of 25.0±1.3% and 1,000 pmtrifluoroethanol (n=3) resulted in an extraction of 1.58±4.0% (FIG. 3,Table 6). Both additives outperform the blank, and additionally, ethanoldisplayed enhanced performance compared to trifluoroethanol (student's ttest, p=0.001).

TABLE 6 Mean bitumen extraction. standard deviation, and number of runsfor the blank, ethanol (1,000 ppm) and trifluoroethanol (1,000 ppm).Number Mean Bitumen Level of Runs Extraction (%) Std Dev Blank 5 6.231.65 Ethanol 3 25.58 1.28 Trifluoroethanol 3 15.76 3.95

TABLE 7 Comparative data with p-values for the blank, ethanol, andtrifluoroethanol. Level −Level p-value Ethanol Blank <.0001* EthanolTrifluoroethanol 0.0010* Trifluoroethanol Blank 0.0006*

Example 6

A comparative study was undertaken looking at C₁-C₅ (methanol-pentanol)straight chain alcohols for their efficacy in enhancing bitumenextraction. All of the alcohols tested were closed at 1,000 ppm anddisplayed enhanced bitumen extraction over the blank (FIG. 4, Table 8).In addition, methanol was outperformed by the other alcohols studied.From this data set, no statistically significant differences in bitumenextraction were observed between ethanol, 1-propanol, 1-butanol and1-pentanol.

TABLE 8 Mean bitumen extraction, standard deviation and number ofexperimental runs completed for C₁-C₅ alcohols. Number of Mean BitumenLevel Runs Extracted (%) Std Dev 1-Butanol 3 29.25 7.28 1-Pentanol 322.82 2.53 1-Propanol 2 24.65 4.65 Blank 5 6.23 1.65 Ethanol 3 25.581.28 Methanol 2 14.58 3.05

TABLE 9 Comparative data with p-values for additives tested. Level−Level p-Value 1-Butanol Blank <.0001* Ethanol Blank <.0001* 1-PropanolBlank <.0001* 1-PentanoI Blank <.0001* 1-Butanol Methanol 0.0009*Ethanol Methanol 0.0068* 1-Propanol Methanol 0.0185* Methanol Blank0.0193* 1-Pentanol Methanol 0.0310* 1-Butanol 1-Pentanol 0.0546

Example 7

A study was conducted looking at various isomers of C₅ alcohols todetermine if any performance difference could be observed. In additionto 1-pentanol previously tested, 2-pentanol, 3-methyl-1-butanol,2-methyl-1-butanol and 2-methyl-2-butanol were run at a dosage of 1,000ppm. No statistically significant performance difference between theseadditives was observed (FIG. 5, Tables 10 & 11).

TABLE 10 Mean bitumen extracted, standard deviation and number ofexperimental runs completed for the C5 alcohol isomers. Number of MeanBitumen Level Runs Extracted (%) Std Dev 1-Pentanol 3 22.82 2.532-methyl-1-butanol 2 22.57 0.021 2-methyl-2-butanol 4 22.83 4.412-Pentanol 3 26.51 6.02 3-methyl-1-butanol 2 19.95 0.028

TABLE 11 Comparative data with p-values for additives tested. Level−Level p-value 2-Pentanol 3-methyl-1-butanol 0.1058 2-Pentanol2-methyl-1-butanol 0.3077 2-Pentanol 1-Pentanol 0.2878 2-Pentanol2-methyl-2-butanol 0.2588 2-methyl-2-butanol 3-methyl-1-butanol 0.42691-Pentanol 3-methyl-1-butanol 0.4512 2-methyl-1-butanol3-methyl-1-butanol 0.5293 2-methyl-2-butanol 2-methyl-1-butanol 0.94071-Pentanol 2-methyl-1-butanol 0.9451 2-methyl-2-butanol 1-Pentanol0.9983

Example 8

Experimental runs were also completed studying alcohol blends (Table12). All of the blends outperformed the blank (mean bitumen extracted of6.2%). Alcohols were also blended with trifluoroethanol (TFE) which alsoresulted in enhanced bitumen extraction (Table 13).

TABLE 12 Bitumen extracted for a blend of three alcohols added in acombined dose of 1,000 ppm. Bitumen Additive Dose (ppm) Extracted (%)Ethanol/Propanol/Butanol 400/400/200 12.68 Ethanol/Propanol/Butanol400/400/200 13.79 Propanol/Butanol/1-Pentanol 400/400/200 22.99Propanol/Butanol/1-Pentanol 400/400/200 20.77

TABLE 13 Bitumen extracted for alcohols blended with trifluoroethanol(TFE). Bitumen Additive Dose (ppm) Extracted (%) TFE/Ethanol 500/50019.05 TFE/Ethanol 500/500 18.06 TFE/Ethanol 200/800 22.53 TFE/Ethanol200/800 25.97 TFE/Butanol 1000/1000 32.08 TFE/Ethanol/Propanol200/400/400 18.63 TFE/Ethanol/Propanol 200/400/400 20.62 TFE/Pentanol500/500 21.49 TFE/Pentanol 500/500 14.91 Ethanol/1-Pentanol 500/50023.81 TFE/Ethanol 1000/500  19.94 TFE/Ethanol  500/1000 14.75TFE/Ethanol 1000/1000 26.23 TFE/Ethanol/1-Pentanol 167/667/167 14.64TFE/Ethanol/1-Pentanol 667/167/167 21.22 TFE/Ethanol/1-Pentanol333/333/333 11.53 TFE/Ethanol/1-Pentanol 167/167/667 15.06 TFE/Ethanol100/900 15.50 TFE/Ethanol 750/250 21.70 TFE/Ethanol 250/750 19.43

All of the compositions and methods disclosed and claimed herein can bemade and executed without undue experimentation in light of the presentdisclosure. While this invention may be embodied in many differentforms, there are described in detail herein specific preferredembodiments of the invention. The present disclosure is anexemplification of the principles of the invention and is not intendedto limit the invention to the particular embodiments illustrated. Inaddition, unless expressly stated to the contrary, use of the term “a”is intended to include “at least one” or “one or more.” For example, “adevice” is intended to include “at least one device” or “one or moredevices.”

Any ranges given either in absolute terms or in approximate terms areintended to encompass both, and any definitions used herein are intendedto be clarifying and not limiting. Notwithstanding that the numericalranges and parameters setting forth the broad scope of the invention areapproximations, the numerical values set forth in the specific examplesare reported as precisely as possible. Any numerical value, however,inherently contains certain errors necessarily resulting from thestandard deviation found in their respective testing measurements.Moreover, all ranges disclosed herein are to be understood to encompassany and all subranges (including all fractional and whole values)subsumed therein.

Furthermore, the invention encompasses any and all possible combinationsof some or all of the various embodiments described herein. It shouldalso be understood, that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the invention and withoutdiminishing its intended advantages. It is therefore intended that suchchanges and modifications be covered by the appended claims.

The claimed invention is:
 1. A composition comprising a hydrocarbon andan injectable mixture of steam, trifluoroethanol, and one or morealcohols selected from ethanol, 1-butanol, 2-pentanol, a mixture ofpropanol and butanol and 1-pentanol, or a mixture of ethanol and1-pentanol.
 2. The composition of claim 1 wherein the alcohol isethanol.
 3. The composition of claim 1 wherein the alcohol is butanol.4. The composition of claim 1 wherein the temperature of the mixture isabout 500° C.
 5. The composition of claim 4 wherein the composition isunder applied pressure.
 6. The composition of claim 5 wherein thecomposition is present in an injector well or in a well head.
 7. Thecomposition of claim 1 wherein the composition is present in a steamchamber, in a steam header, or in a boiler feed.
 8. A compositioncomprising a hydrocarbon and a mixture consisting of steam,trifluoroethanol, and one or more alcohols selected from ethanol,1-butanol, 2-pentanol, a mixture of propanol and butanol and 1-pentanol,or a mixture of ethanol and 1-pentanol.
 9. The composition of claim 8wherein the alcohol is ethanol.
 10. The composition of claim 8 whereinthe alcohol is butanol.
 11. The composition of claim 8 wherein thetemperature of the mixture is about 500° C.
 12. The composition of claim8 wherein the composition is under applied pressure.
 13. The compositionof claim 8 wherein the composition is present in an injector well or ina well head.
 14. The composition of claim 8 wherein the composition ispresent in a steam chamber, in a steam header, or in a boiler feed.